Marantz 1152DC Manual

The Marantz 1152DC is a classic stereo receiver featuring DC amplifier design, 32 watts per channel RMS power output, phono input for turntables, tape monitor circuits, loudness contour, high and low filters, and distinctive Marantz tuning meter. Below are key sections for features, installation, operation, specifications, and maintenance.

1. Features at a Glance 2. Installation 3. Operation 4. Specifications 5. Controls and Functions 6. Connecting Components 7. Tuning and Reception 8. Maintenance 9. Technical Information 10. Troubleshooting

Features at a Glance

Key components: DC power amplifier, tuning meter, speaker selector, tone controls, input selector.

Feature	Description
Power Output	32 watts per channel RMS (8 ohms)
DC Amplifier	Direct-coupled amplifier design
Tuning Meter	Signal strength and center tuning indicator
Input Selector	Phono, Aux, Tuner, Tape 1, Tape 2
Tone Controls	Bass and treble adjustment
Filters	High and low frequency filters
Loudness Contour	Compensates for low volume listening
Speaker Selectors	A/B speaker selection
Tape Monitor	Tape recording and playback circuits
Headphone Jack	For private listening

Installation

Unpack and inspect contents. Place on stable, well-ventilated surface.

Connect speakers: Use speaker wire to connect to A or B speaker terminals.
Connect turntable: Use phono input for magnetic cartridges.
Connect other sources: Use Aux input for CD players, tuners, etc.
Connect tape decks: Use Tape 1 and Tape 2 inputs/outputs.
Plug into AC power outlet.

WARNING! Ensure proper ventilation; do not block ventilation slots. Use correct speaker impedance.

Operation

Power on receiver; select input source.

Input selection: Rotate INPUT SELECTOR to desired source (Phono, Aux, Tuner).
Volume control: Adjust MAIN VOLUME knob to desired listening level.
Tone adjustment: Use BASS and TREBLE controls to suit listening preference.
Loudness: Engage LOUDNESS switch for enhanced bass at low volumes.
Filters: Use HIGH and LOW filters to reduce noise.

CAUTION! Avoid excessive volume levels to prevent speaker damage.

Specifications

Power Output: 32 watts per channel RMS at 8 ohms
Frequency Response: 10Hz - 50kHz
Total Harmonic Distortion: 0.08%
Input Sensitivity: Phono: 2.5mV, Aux: 150mV
Signal-to-Noise Ratio: Phono: 76dB, Aux: 90dB
Tone Controls: Bass: ±10dB at 100Hz, Treble: ±10dB at 10kHz
Power Requirements: 120V AC, 60Hz
Dimensions: 17-1/4" W × 5-1/4" H × 13-3/4" D
Weight: 21 lbs

Controls and Functions

Front Panel: POWER switch, INPUT SELECTOR, VOLUME, BASS, TREBLE, BALANCE, LOUDNESS, FILTERS, TUNING, SPEAKER SELECTORS.

Rear Panel: AC power cord, antenna terminals, phono/aux/tuner inputs, tape inputs/outputs, speaker terminals.

Tone Controls: Bass and treble adjustment with center detent. Filters: High filter reduces hiss, low filter reduces rumble. Loudness: Compensates for Fletcher-Munson curves. Speaker Selectors: A/B for multiple speaker pairs.

Connecting Components

Phono: For turntables with magnetic cartridges. Aux: For CD players, tape decks. Tuner: For external tuners.

Turn off receiver before connecting components.
Match cable types to appropriate inputs.
Ensure proper grounding for phono connections.
Use high-quality interconnects for best performance.

Tip: Keep signal cables away from power cords to reduce hum.

Tuning and Reception

AM/FM stereo tuner with tuning meter.

Select TUNER input on selector.
Rotate TUNING knob while watching tuning meter.
Center meter needle for strongest signal and lowest distortion.
For FM stereo, ensure stereo indicator lights.
Use external antenna for improved reception.

Note: Tuning meter indicates both signal strength and center tuning.

Maintenance

Unplug before cleaning. Use soft, dry cloth only; avoid liquids.

Clean controls with contact cleaner if scratchy operation occurs.

CAUTION! Do not use abrasive cleaners. Keep away from moisture.

Technical Information

DC amplifier design provides excellent transient response and low distortion. Direct coupling eliminates coupling capacitors in signal path. Marantz proprietary circuitry ensures high damping factor and stable operation.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound	Speaker connections/input selection	Check speaker wires; verify input selector position; check volume level.
Hum or noise	Grounding/cable issues	Ensure proper phono ground; separate signal and power cables.
Distorted sound	Overload/speaker impedance	Reduce volume; check speaker impedance matches requirements.
One channel dead	Connection/balance control	Check balance control centered; verify connections; try other inputs.
Poor FM reception	Antenna/tuning	Use external antenna; ensure proper tuning meter alignment.

Service: Consult qualified technician for internal repairs.